Battery SOC estimation method and device

Abstract

The present invention provides a battery SOC estimation method and device, which includes: collecting charge and discharge currents at a preset sampling period and obtaining the current battery capacity corresponding to the charge and discharge currents; calculating the current integral capacity corresponding to the charge and discharge currents; determining the corresponding current battery capacity weight and current integral capacity weight based on whether the charge and discharge currents meet the corresponding preset current range; and calculating the actual remaining capacity corresponding to the charge and discharge current based on the current battery capacity, current battery capacity weight, current integral capacity, and current integral capacity weight corresponding to the charge and discharge currents. By using a weight distribution method, the accuracy of estimating the actual remaining capacity of the battery is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power battery remaining capacity calculation, and in particular to a battery SOC estimation method and device. Background Art

[0002] The development of the new energy vehicle industry is inseparable from the use of power batteries. To effectively utilize power batteries, a battery management system (BMS) is needed to monitor battery status, protect batteries, and control charge and discharge, keeping the batteries in optimal condition. Monitoring the battery's current remaining capacity (SOC) is particularly important.

[0003] Battery SOC, or state of charge, reflects the remaining capacity of a battery. Its numerical value is defined as the ratio of remaining capacity to battery capacity, often expressed as a percentage. Its value ranges from 0 to 1, with SOC = 0 indicating a fully discharged battery and SOC = 1 indicating a fully charged battery. Battery SOC cannot be measured directly; it can only be estimated using parameters such as battery terminal voltage, charge / discharge current, and internal resistance. These parameters are also affected by numerous uncertainties, including battery aging, ambient temperature fluctuations, and vehicle driving conditions. Therefore, accurate SOC estimation has become a pressing issue in the development of electric vehicles. Summary of the Invention

[0004] Therefore, the present invention aims to solve the technical problem of inaccurate SOC estimation in the prior art, thereby providing a battery SOC estimation method and device.

[0005] According to a first aspect, an embodiment of the present invention provides a battery SOC estimation method, comprising the following steps:

[0006] Collecting the charge and discharge current at a preset sampling period and obtaining the current battery capacity corresponding to the charge and discharge current;

[0007] Calculating the current integrated capacity corresponding to the charge and discharge current;

[0008] Determining the corresponding current battery capacity weight and current integrated capacity weight according to whether the charge and discharge current meets the corresponding preset current range;

[0009] The actual remaining capacity corresponding to the charge and discharge current is calculated according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight.

[0010] Optionally, determining the corresponding weight of the current battery capacity and the weight of the current integrated capacity according to whether the charge and discharge current meets a corresponding preset current range includes:

[0011] Under the condition that the first preset current range is determined to be satisfied, the weight of the corresponding current battery capacity is determined to be 0, and the weight of the current integrated capacity is determined to be 1;

[0012] If the charge and discharge currents collected m times consecutively satisfy the second preset current range, the weight of the current battery capacity corresponding to each of the charge and discharge currents collected m times consecutively is (m-1)*d, and the weight of the current integrated capacity corresponding to each of the charge and discharge currents collected m times consecutively is 1-(m-1)*d, where d is a constant;

[0013] If the charge and discharge currents collected n times consecutively satisfy the third preset current range, the weight of the current battery capacity corresponding to each of the charge and discharge currents collected n times consecutively is n*k, and the weight of the current integrated capacity corresponding to each of the charge and discharge currents collected n times consecutively is 1-n*k, where k is a constant and k is greater than d;

[0014] The current in the second preset current range is smaller than the current in the first preset current range. The current in the third preset current range is smaller than the current in the second preset current range.

[0015] Optionally, calculating the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight includes:

[0016] Using a preset mathematical model, the actual remaining capacity corresponding to each collected charge and discharge current is calculated based on the current battery capacity, current battery capacity weight, current integrated capacity, and current integrated capacity weight corresponding to each collected charge and discharge current;

[0017] The preset mathematical model is:

[0018] SOC(i)=SOC(OCV i )×W+SOC(SOC i )×(1-W)

[0019] Among them, i is the charge and discharge current of the battery to be tested, SOC(i) is the actual remaining capacity corresponding to the charge and discharge current i, SOC(OCV i ) is the current battery capacity corresponding to the charge and discharge current i, SOC (SOC i) is the current integrated capacity corresponding to the charge and discharge current i, W is the weight of the current battery capacity corresponding to the charge and discharge current i, and 1-W is the weight of the current integrated capacity corresponding to the charge and discharge current i.

[0020] Optionally, under the condition that the charge and discharge currents collected for m consecutive times meet the second preset current range, when the weight of the current battery capacity corresponding to the charge and discharge current collected for the pth time reaches the weight threshold of the preset battery capacity, then the weights of the current battery capacity corresponding to the charge and discharge current collected for the [(p+1), m]th time are all the weight threshold of the preset battery capacity.

[0021] Optionally, under the condition that the charge and discharge currents collected for n consecutive times satisfy the third preset current range, when the weight of the current battery capacity corresponding to the charge and discharge current collected for the qth time reaches 1, the weights of the current battery capacity corresponding to the charge and discharge current collected for the [(q+1), n]th time are all 1.

[0022] Optionally, the first preset current range is 1 / 3C to 1C; the second preset current range is 1 / 20C to 1 / 3C; and the third preset current range is 0 to 1 / 20C.

[0023] Optionally, the charge and discharge current includes a current value and a current direction.

[0024] According to a second aspect, an embodiment of the present invention provides a battery SOC estimation device, comprising:

[0025] An acquisition module is used to collect the charge and discharge current at a preset sampling period and obtain the current battery capacity corresponding to the charge and discharge current;

[0026] An integration module, used to calculate the current integral capacity corresponding to the charge and discharge current;

[0027] a judgment module, configured to determine a corresponding current battery capacity weight and a current integrated capacity weight according to whether the charge and discharge current meets a corresponding preset current range;

[0028] The calculation module is used to calculate the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight.

[0029] According to the third aspect, an embodiment of the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the above-mentioned battery SOC estimation method by executing the computer instructions.

[0030] According to a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the above-mentioned battery SOC estimation method.

[0031] The technical solution of the present invention has the following advantages:

[0032] In an embodiment of the present invention, the charge and discharge currents are first collected according to a preset sampling period, the charge and discharge current corresponding to each collection moment is obtained, the corresponding current battery capacity is obtained, and the corresponding current integrated capacity is calculated. Secondly, the weight of the current battery capacity and the weight of the current integrated capacity are determined based on the preset current range satisfied by the collected charge and discharge currents. Finally, the actual remaining capacity corresponding to the charge and discharge current is calculated based on the current battery capacity, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight. This actual remaining capacity estimation method addresses the inaccurate battery remaining capacity estimation problem in the prior art. By determining the preset range of the collected current based on the current, the current battery capacity weight and the current integrated capacity weight are determined. This weighting method significantly improves the accuracy of the actual remaining capacity estimation of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 This is a flowchart of a specific example of a battery SOC estimation method in embodiment 1 of the present invention;

[0035] Figure 2 A graph showing a specific example of a relationship between the open circuit voltage of the battery under test and the current ideal battery capacity during the charging process in Example 1 of the present invention;

[0036] Figure 3 A graph showing a specific example of a relationship between the open circuit voltage of the battery under test and the current ideal battery capacity during the discharge process in Example 1 of the present invention;

[0037] Figure 4 This is a principle block diagram of a specific example of a battery SOC estimation device in embodiment 2 of the present invention;

[0038] Figure 5This is a structural diagram of a specific example of a computer device in Example 3 of the present invention. DETAILED DESCRIPTION

[0039] The technical solutions of the present invention are described clearly and completely below with reference to the accompanying drawings. It should be understood that the embodiments described herein are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0040] In the description of the present invention, it should be noted that terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; internal communication between two components; and wireless or wired connections. Those skilled in the art will understand the specific meanings of these terms in the present invention.

[0042] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] Example 1

[0044] This embodiment provides a battery SOC estimation method, which can first collect the charge and discharge current and voltage signals of the battery to be tested by hardware equipment such as circuit detection, and then calculate, judge and output data based on the collected data through equipment such as a server, and finally program the estimation method into the battery charging and discharging equipment or other equipment for detecting the battery SOC, thereby realizing the estimation of the battery SOC during the charge and discharge process of the battery to be tested, such as Figure 1 As shown, the following steps are included:

[0045] Step S101 : collecting the charge and discharge currents at a preset sampling period, and obtaining the current battery capacity corresponding to the charge and discharge currents.

[0046] The battery under test referred to in this embodiment can be a lithium battery, lead-acid battery, or nickel-cadmium battery used in new energy vehicles. During the battery's charge and discharge process, a constant charge and discharge current can be obtained based on the battery's rated capacity, charge and discharge rate, charge and discharge time, etc. During the charge and discharge process, the battery is often first rapidly charged and discharged with a constant current, then the charging current is gradually reduced, and finally a trickle current is used for charging and discharging.

[0047] However, during the actual charging and discharging process of the battery, the current will fluctuate to varying degrees. For smaller charging and discharging currents, this current fluctuation will increase the error in charging and discharging current collection, thereby resulting in inaccurate estimation of the actual remaining battery capacity.

[0048] Therefore, in an embodiment of the present invention, the charge and discharge current of the battery to be tested is first collected using a preset sampling period, and the preset sampling period may be 100ms, 200ms, etc. Take a sampling period of sampling every 100ms as an example, that is, it can be collected once at the initial moment of 0ms, once at the 100ms, once at the 200ms... once at the 1min, etc. Each collection moment corresponds to the charge and discharge current collected. Furthermore, while collecting the charge and discharge current, the battery open circuit voltage (OCV) corresponding to each sampling period can also be obtained. The battery open circuit voltage is the potential difference between the positive and negative electrodes of the battery when it is at rest. The current ideal battery capacity is determined based on the obtained current open circuit voltage and the SOC_OCV curve. The SOC_OCV curve is the curve relationship between the battery open circuit voltage and the battery capacity at different rates obtained during the capacity test, such as Figure 2 and Figure 3 As shown, Figure 2 It is the curve relationship between the open circuit voltage of the battery under test and the current ideal battery capacity during the charging process. Figure 3 The curve relationship between the open circuit voltage of the battery under test and the current ideal battery capacity during the discharge process is shown in Figure 1. In this embodiment, the current battery capacity can be the current ideal battery capacity. In other words, each acquisition moment corresponds not only to the collected charge and discharge current, but also to the current battery capacity.

[0049] Step S102: calculating the current integrated capacity corresponding to the charge and discharge current.

[0050] The current integrated capacity can be calculated based on the battery's charge and discharge current using an ampere-hour integration algorithm. Essentially, the ampere-hour integration algorithm estimates the battery's remaining capacity by accumulating the amount of electricity charged or discharged during charging or discharging. In other words, the remaining capacity of the battery is estimated by integrating time and current. The remaining capacity of the battery estimated using the ampere-hour integration algorithm is the current integrated capacity in this embodiment. In this embodiment, since the charge and discharge currents are collected according to a preset sampling period, the current integrated capacity corresponding to each sampling period can be estimated using the ampere-hour integration algorithm.

[0051] Step S103 , determining the corresponding current battery capacity weight and current integrated capacity weight according to whether the charge and discharge current meets the corresponding preset current range.

[0052] As described above, during the charge and discharge process of the battery to be tested, not only the current battery capacity corresponding to each acquisition moment can be obtained, but also the current integrated capacity corresponding to each sampling period can be estimated using the ampere-hour integration algorithm.

[0053] Regarding the current battery capacity, since the current battery capacity is directly related to the battery open circuit voltage (OCV), and the battery open circuit voltage is prone to polarization when the charge and discharge current is large, and the electrode deviates from the equilibrium electrode potential, the battery open circuit voltage obtained when the charge and discharge current is large is not accurate, and the corresponding current battery capacity cannot represent the actual remaining capacity of the battery.

[0054] Regarding current integrated capacity, since its calculation is directly related to current, current fluctuates to varying degrees during the actual battery charge and discharge process. For high charge and discharge currents, current fluctuations will not significantly affect the charge and discharge current collected during each sampling cycle. However, for low charge and discharge currents, even small current fluctuations can affect the collected charge and discharge current results. If the collected charge and discharge currents have large errors, the current integrated capacity estimated using the ampere-hour integration algorithm will also have large errors. Therefore, the current integrated capacity cannot represent the actual remaining capacity of the battery.

[0055] There are technical problems with the current battery capacity and current integral capacity that are inaccurate. Therefore, in this embodiment, the corresponding current battery capacity weight and current integral capacity weight will be determined based on the corresponding preset current range satisfied by the charging and discharging current. The specific method for determining the current battery capacity weight and current integral capacity weight will be introduced below.

[0056] Because the determination of the current battery capacity and the current integrated capacity are both related to the current, and current fluctuations and high currents can cause battery polarization, the remaining battery capacity represented by the current battery capacity and the current integrated capacity are not accurate. However, when the charge and discharge current is low, the current battery capacity corresponding to the battery open circuit voltage value is more accurate, and when the charge and discharge current is high, the current integrated capacity is more accurate. Therefore, the embodiment of the present invention determines the weight of the current battery capacity and the weight of the current integrated capacity based on the size of the charge and discharge current and the preset current range within which the collected charge and discharge current falls. This can greatly improve the accuracy of the remaining battery capacity estimation.

[0057] Step S104 , calculating the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight.

[0058] As mentioned above, each acquisition moment corresponds not only to the collected charge and discharge current, but also to the current battery capacity and the current integrated capacity corresponding to each sampling period estimated using the ampere-hour integration algorithm. Since the current battery capacity and current integrated capacity are both related to current, the current battery capacity weight and current integrated capacity weight are determined based on the collected charge and discharge current. A preset mathematical model is then used to calculate the actual remaining capacity corresponding to each collected charge and discharge current.

[0059] In this embodiment, first, the charge and discharge current is collected according to a preset sampling period to obtain the charge and discharge current corresponding to each collection moment, and the corresponding current battery capacity is obtained, and the corresponding current integrated capacity is calculated. Secondly, based on the preset current range satisfied by the collected charge and discharge current, the corresponding current battery capacity weight and current integrated capacity weight are determined. Finally, based on the current battery capacity, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight, the actual remaining capacity corresponding to the charge and discharge current is calculated. This actual remaining capacity estimation method addresses the problem of inaccurate battery remaining capacity estimation in the prior art. By determining the preset range of the current based on the collected current, the current battery capacity weight and the current integrated capacity weight are determined respectively. Through the weight allocation method, the accuracy of the battery's actual remaining capacity estimation is greatly improved.

[0060] As an optional implementation manner, in an embodiment of the present invention, determining the corresponding weight of the current battery capacity and the weight of the current integrated capacity according to whether the charge and discharge current meets the corresponding preset current range includes:

[0061] Under the condition that the first preset current range is determined to be met, the weight of the corresponding current battery capacity is determined to be 0, and the weight of the current integrated capacity is determined to be 1.

[0062] During the charging process, batteries are often first rapidly charged with a high current, followed by continuous charging, where the charging current gradually decreases to ensure the battery reaches the critical state of full charge, and finally trickle charging, where weak pulses of current are used to charge the battery until it is fully saturated. Similarly, during the discharge process, batteries are often first rapidly discharged with a high current, followed by continuous discharge, where the charging current gradually decreases to ensure the battery reaches the critical state of full discharge, and finally discharged with a low current until the battery is fully discharged.

[0063] In this embodiment, the first preset current range can be set to 1 / 3C to 1C (including 1C), that is, a preset large current range. As mentioned above, when the charge and discharge current of the battery is a large current, the battery is prone to polarization, and the electrode deviates from the equilibrium electrode potential, resulting in an inaccurate open circuit voltage of the battery, thereby causing the current battery capacity to be inaccurate. However, for current fluctuations in the case of large charge and discharge currents, a large error will not be generated in the charge and discharge current collected in each sampling cycle. Therefore, in the case of large currents, in this embodiment, that is, the current within the first preset current range of 1 / 3C to 1C, the weight of the current battery capacity can be set to 0, and the weight of the current integral capacity can be set to 1. That is, the remaining capacity of the battery under the charge and discharge current conditions in the first preset current range can be completely calculated using the current integral capacity.

[0064] If the charge and discharge currents collected m times consecutively satisfy the second preset current range, the weight of the current battery capacity corresponding to each of the charge and discharge currents collected m times consecutively is (m-1)*d, and the weight of the current integrated capacity corresponding to each of the charge and discharge currents collected m times consecutively is 1-(m-1)*d, where d is a constant;

[0065] In this embodiment, the second preset current range can be set to 1 / 20C to 1 / 3C (inclusive). Furthermore, when the continuously collected charge and discharge currents are all within the second preset current range, the current battery capacity weight is increased by d per cycle, where d can be 1%. This is because when the current decreases from less than 1 / 3C to approaching zero after a few seconds, a confidence percentage above 1% will affect the current battery capacity weight.

[0066] Specifically, taking d as 1% as an example, for example, the current collected at T1 is 1 / 2C, the current collected at T2 is 1 / 11C, the current collected at T3 is 1 / 9C, the current collected at T4 is 1 / 9C, and the current collected at T5 is 1 / 21C. At this time, the charge and discharge currents collected for three consecutive times (T2, T3, and T4) all meet the second preset current range. The weight of the current battery capacity corresponding to the charge and discharge current collected at T2 is (m-1)*d, which is 0, the weight of the current battery capacity corresponding to the charge and discharge current collected at T3 is (m-1)*d, which is 1*1%, which is 1%, and the weight of the current battery capacity corresponding to the charge and discharge current collected at T4 is (m-1)*d, which is 2*1%, which is 2%.

[0067] Correspondingly, the weight of the current integral capacity corresponding to the charge and discharge current collected at time T2 is 1- (m-1)*d, which is 1; the weight of the current integral capacity corresponding to the charge and discharge current collected at time T3 is (m-1)*d, that is, 1-1*1%, which is 99%; the weight of the current integral capacity corresponding to the charge and discharge current collected at time T4 is 1-(m-1)*d, which is 98%.

[0068] Furthermore, in this embodiment, the weight of the current battery capacity (m-1)*d does not exceed 30%. If the weight of the current battery capacity (m-1)*d is 30%, it is maintained at 30%. This prevents the problem of completely "trusting" the weight of the current battery capacity within the second preset current range, resulting in inaccurate calculation of the actual remaining battery capacity.

[0069] When the continuously collected charge and discharge current is not within the second preset current range, the current battery capacity weight is reset to 0 and the current integral capacity weight is reset to 1 until the continuously collected charge and discharge current is all within the second preset current range.

[0070] If the charge and discharge currents collected n times consecutively satisfy the third preset current range, the weight of the current battery capacity corresponding to each of the charge and discharge currents collected n times consecutively is n*k, and the weight of the current integrated capacity corresponding to each of the charge and discharge currents collected n times consecutively is 1-n*k, where k is a constant and k is greater than d;

[0071] In this embodiment, the third preset current range can be set to 0 to 1 / 20C (including 1 / 20C). Furthermore, when the continuously collected charge and discharge currents are all within the third preset current range, it is set to collect once per cycle, and the weight of the current battery capacity is increased by k, k can be 2%, where k is greater than d. The calculation method of the weight of the current battery capacity and the weight of the current integral capacity within the third preset current range is the same as the calculation method of the second preset current range, and will not be repeated here. In the case of low current, you can "trust" more of the current battery capacity until you completely "trust" the current battery capacity, thereby calculating a more accurate actual remaining battery capacity.

[0072] Furthermore, when the continuously collected charge and discharge current is not within the third preset current range, the current battery capacity weight is reset to k, which is 2% in this embodiment. When the continuously collected charge and discharge current is again within the third preset current range, the current battery capacity weight is still k for the first time, ensuring that the actual remaining capacity calculated at each moment is relatively stable.

[0073] The current in the second preset current range is smaller than the current in the first preset current range. The current in the third preset current range is smaller than the current in the second preset current range.

[0074] In this embodiment, the influence of current on the current battery capacity and the current integrated capacity is fully considered. By determining the weight of the current battery capacity and the weight of the current integrated capacity under different current conditions, the actual remaining capacity of the battery is calculated more accurately.

[0075] As an optional implementation manner, in an embodiment of the present invention, calculating the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight includes:

[0076] Using a preset mathematical model, the actual remaining capacity corresponding to each collected charge and discharge current is calculated based on the current battery capacity, current battery capacity weight, current integral capacity, and current integral capacity weight corresponding to each collected charge and discharge current;

[0077] The preset mathematical model is:

[0078] SOC(i)=SOC(OCV i )×W+SOC(SOC i )×(1-W)

[0079] Among them, i is the charge and discharge current of the battery to be tested, SOC(i) is the actual remaining capacity corresponding to the charge and discharge current i, SOC(OCV i) is the current battery capacity corresponding to the charge and discharge current i, SOC (SOC i ) is the current integrated capacity corresponding to the charge and discharge current i, W is the weight of the current battery capacity corresponding to the charge and discharge current i, and 1-W is the weight of the current integrated capacity corresponding to the charge and discharge current i.

[0080] In this embodiment, based on the charge and discharge current collected at each moment and combined with the preset current range, the weight of the current battery capacity and the weight of the current integral capacity at each moment are determined, and the product of the current battery capacity and the current battery capacity weight and the product of the current integral capacity and the current integral capacity weight are added together to calculate a more accurate actual remaining battery capacity corresponding to each moment.

[0081] As an optional implementation, in an embodiment of the present invention, under the condition that the charge and discharge currents collected for m consecutive times meet the second preset current range, when the weight of the current battery capacity corresponding to the charge and discharge current collected for the pth time reaches the weight threshold of the preset battery capacity, then the weights of the current battery capacity corresponding to the charge and discharge current collected for the [(p+1), m]th time are all the weight threshold of the preset battery capacity.

[0082] In this embodiment, the preset battery capacity weight threshold may be the maximum value of the weight of the current battery capacity within the second preset current range. Furthermore, in this embodiment, the preset battery capacity weight threshold may be set to 30%. When the weight of the current battery capacity (m-1)*d reaches 30%, the weight of the current battery capacity at the p+1th time remains at 30%. This prevents the problem of completely "trusting" the weight of the current battery capacity within the second preset current range, resulting in inaccurate calculation of the actual remaining battery capacity.

[0083] As an optional implementation, in an embodiment of the present invention, under the condition that the charge and discharge currents collected for n consecutive times meet the third preset current range, when the weight of the current battery capacity corresponding to the charge and discharge current collected for the qth time reaches 1, the weight of the current battery capacity corresponding to the charge and discharge current collected for the [(q+1), n]th time is all 1.

[0084] That is to say, when the weight n*k of the current battery capacity reaches 1, the weight of the current battery capacity at the q+1th time remains 1, which means that the current battery capacity is fully "trusted".

[0085] As an optional implementation, in the embodiment of the present invention,

[0086] The first preset current range is 1 / 3C to 1C;

[0087] The second preset current range is 1 / 20C to 1 / 3C;

[0088] The third preset current range is 0 to 1 / 20 C, where C is the unit of charge, coulomb.

[0089] As an optional embodiment, in an embodiment of the present invention, the charge and discharge current includes a current value and a current direction. The SOC estimation method in this embodiment is applicable not only to battery charging but also to battery discharging. The SOC estimation method in this embodiment can effectively improve the accuracy of estimating the actual remaining capacity of the battery.

[0090] Example 2

[0091] This embodiment provides a battery SOC estimation device, which can be used to execute the battery SOC estimation method in the above embodiment 1. The device can be set inside a server or other device, and the modules cooperate with each other to achieve battery SOC estimation, such as Figure 4 As shown, the device includes:

[0092] An acquisition module 201 is configured to collect the charge and discharge current at a preset sampling period and obtain the current battery capacity corresponding to the charge and discharge current;

[0093] An integration module 202 is configured to calculate the current integral capacity corresponding to the charge and discharge current;

[0094] A judgment module 203 is configured to determine a corresponding current battery capacity weight and a current integrated capacity weight according to whether the charge and discharge current meets a corresponding preset current range;

[0095] The calculation module 204 is configured to calculate the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight.

[0096] In this embodiment, first, the charge and discharge current is collected according to a preset sampling period to obtain the charge and discharge current corresponding to each collection moment, and the corresponding current battery capacity is obtained, and the corresponding current integrated capacity is calculated. Secondly, based on the preset current range satisfied by the collected charge and discharge current, the corresponding current battery capacity weight and current integrated capacity weight are determined. Finally, based on the current battery capacity, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight, the actual remaining capacity corresponding to the charge and discharge current is calculated. This actual remaining capacity estimation method addresses the problem of inaccurate battery remaining capacity estimation in the prior art. By determining the preset range of the current based on the collected current, the current battery capacity weight and the current integrated capacity weight are determined respectively. Through the weight allocation method, the accuracy of the battery's actual remaining capacity estimation is greatly improved.

[0097] For a detailed description of the above-mentioned device part, please refer to the above-mentioned method embodiment, which will not be repeated here.

[0098] Example 3

[0099] This embodiment provides a computer device, such as Figure 5 As shown, the computer device includes a processor 301 and a memory 302, wherein the processor 301 and the memory 302 can be connected via a bus or other means. Figure 5 The bus connection is taken as an example.

[0100] The processor 301 may be a central processing unit (CPU). The processor 301 may also be other general-purpose processors, digital signal processors (DSP), graphics processing units (GPU), embedded neural network processors (NPU), or other dedicated deep learning coprocessors, application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0101] Memory 302, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the corresponding program instructions / modules for the battery SOC estimation method in the embodiments of the present invention. Processor 301 executes the non-transitory software programs, instructions, and modules stored in memory 302 to perform various processor functions and data processing, thereby implementing the battery SOC estimation method in the above-mentioned method embodiment.

[0102] The memory 302 may also include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created by the processor 301, etc. In addition, the memory 302 may include a high-speed random access memory and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 302 may optionally include a memory remotely located relative to the processor 301, and these remote memories may be connected to the processor 301 via a network. Examples of the aforementioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0103] The memory 302 stores one or more modules, which, when executed by the processor 301, perform the following operations: Figure 1 The battery SOC estimation method in the illustrated embodiment.

[0104] For details of the above computer equipment, please refer to Figure 1 The corresponding descriptions and effects in the embodiments shown can be understood and will not be repeated here.

[0105] An embodiment of the present invention further provides a computer-readable storage medium storing computer-executable instructions capable of executing the battery SOC estimation method of any of the above embodiments. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD); the storage medium may also include a combination of the above types of memory.

[0106] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A battery SOC estimation method, characterized in that: The steps include: Collecting the charge and discharge current at a preset sampling period and obtaining the current battery capacity corresponding to the charge and discharge current; Calculating the current integrated capacity corresponding to the charge and discharge current; Determining the corresponding current battery capacity weight and current integrated capacity weight according to whether the charge and discharge current meets the corresponding preset current range; Calculating the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight; The determining of the corresponding weight of the current battery capacity and the weight of the current integrated capacity according to whether the charge and discharge current meets the corresponding preset current range includes: Under the condition that the first preset current range is determined to be satisfied, the weight of the corresponding current battery capacity is determined to be 0, and the weight of the current integrated capacity is determined to be 1; If the charge and discharge currents collected m times consecutively satisfy the second preset current range, the weight of the current battery capacity corresponding to each of the charge and discharge currents collected m times consecutively is (m-1)*d, and the weight of the current integrated capacity corresponding to each of the charge and discharge currents collected m times consecutively is 1-(m-1)*d, where d is a constant; If the charge and discharge currents collected n times consecutively satisfy the third preset current range, the weight of the current battery capacity corresponding to each of the charge and discharge currents collected n times consecutively is n*k, and the weight of the current integrated capacity corresponding to each of the charge and discharge currents collected n times consecutively is 1-n*k, where k is a constant and k is greater than d; The current in the second preset current range is smaller than the current in the first preset current range, and the current in the third preset current range is smaller than the current in the second preset current range.

2. The battery SOC estimation method according to claim 1, characterized in that: Calculating the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight, including: Using a preset mathematical model, the actual remaining capacity corresponding to each collected charge and discharge current is calculated based on the current battery capacity, current battery capacity weight, current integral capacity, and current integral capacity weight corresponding to each collected charge and discharge current; The preset mathematical model is: SOC(i)=SOC(OCV i )×W+SOC(SOC i )×(1-W) Among them, i is the charge and discharge current of the battery to be tested, SOC(i) is the actual remaining capacity corresponding to the charge and discharge current i, SOC(OCV i ) is the current battery capacity corresponding to the charge and discharge current i, SOC (SOC i ) is the current integrated capacity corresponding to the charge and discharge current i, W is the weight of the current battery capacity corresponding to the charge and discharge current i, and 1-W is the weight of the current integrated capacity corresponding to the charge and discharge current i.

3. The battery SOC estimation method according to claim 1, characterized in that: Under the condition that the charge and discharge currents collected for m consecutive times meet the second preset current range, when the weight of the current battery capacity corresponding to the charge and discharge current collected for the pth time reaches the weight threshold of the preset battery capacity, then the weights of the current battery capacity corresponding to the charge and discharge current collected for the [(p+1), m]th time are all the weight threshold of the preset battery capacity.

4. The battery SOC estimation method according to claim 1, characterized in that: Under the condition that the charge and discharge currents collected for n consecutive times meet the third preset current range, when the weight of the current battery capacity corresponding to the charge and discharge current collected for the qth time reaches 1, the weights of the current battery capacity corresponding to the charge and discharge current collected for the [(q+1), n]th time are all 1.

5. The battery SOC estimation method according to claim 1, characterized in that: The first preset current range is 1 / 3C to 1C; The second preset current range is 1 / 20C to 1 / 3C; The third preset current range is 0 to 1 / 20C.

6. The battery SOC estimation method according to any one of claims 1 to 5, characterized in that: The charge and discharge current includes a current value and a current direction.

7. A battery SOC estimation device, characterized in that: include: An acquisition module is used to collect the charge and discharge current at a preset sampling period and obtain the current battery capacity corresponding to the charge and discharge current; An integration module, used to calculate the current integral capacity corresponding to the charge and discharge current; A judgment module, configured to determine a corresponding current battery capacity weight and a current integral capacity weight according to whether the charge and discharge current meets a corresponding preset current range; Wherein, it includes: under the condition of determining that the first preset current range is met, determining that the weight of the corresponding current battery capacity is 0, and the weight of the current integral capacity is 1; if the charge and discharge current collected m times continuously meets the second preset current range, then the weight of the current battery capacity corresponding to the charge and discharge current collected each time in the m consecutive times is (m-1)*d, and the weight of the current integral capacity corresponding to the charge and discharge current collected each time in the m consecutive times is 1-(m-1)*d, where d is a constant; if the charge and discharge current collected n times continuously meets the third preset current range, then the weight of the current battery capacity corresponding to the charge and discharge current collected each time in the n consecutive times is n*k, and the weight of the current integral capacity corresponding to the charge and discharge current collected each time in the n consecutive times is 1-n*k, where k is a constant, and k is greater than d; the current in the second preset current range is less than the current in the first preset current range, and the current in the third preset current range is less than the current in the second preset current range; The calculation module is used to calculate the actual remaining capacity corresponding to the charge and discharge current according to the current battery capacity corresponding to the charge and discharge current, the current battery capacity weight, the current integrated capacity, and the current integrated capacity weight.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the battery SOC estimation method according to any one of claims 1 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the battery SOC estimation method according to any one of claims 1 to 6.

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